package com.taotao.complier.calcu.lex;


public class CharTypes {
    /**
     * 文件结束符
     *
     * End of input character. Used as a sentinel to denote the character one beyond the last defined character in a
     * source file.
     */
    final static byte EOF = 0x1A;


    /**
     * 是否数字
     *
     * @param c
     * @return
     */
    public static boolean isDigit(char c) {
        return c >= '0' && c <= '9';
    }

    private final static boolean[] firstIdentifierFlags = new boolean[256];

    static {
        for (char c = 0; c < firstIdentifierFlags.length; ++c) {
            if (c >= 'A' && c <= 'Z') {
                firstIdentifierFlags[c] = true;
            } else if (c >= 'a' && c <= 'z') {
                firstIdentifierFlags[c] = true;
            }
        }
        firstIdentifierFlags['_'] = true;

        // `是sql的,$是java等语言的
//        firstIdentifierFlags['`'] = true;
//        firstIdentifierFlags['$'] = true;
    }







}
